Long-Term Testing

Long-term testing in animals ranges in duration from a few weeks to several years. Some animal testing continues
after human tests begin to learn whether long-term use of a drug may cause cancer or birth defects. Much of this
information is submitted to FDA when a sponsor requests to proceed with human clinical trials. The FDA reviews the
preclinical research data and then makes a decision as to whether to allow the clinical trials to proceed (see Clinical
Studies (Overview)).